The present invention relates to a suspension strut or damper for a motor vehicle.
Known suspension struts comprise a tube; a piston sealably slidably mounted in the tube and attached to a piston rod, the piston separating a compression chamber from a rebound chamber within the tube; a compression stroke valve mounted on the piston; and a rebound stroke valve mounted on the piston. The compression stroke valve acts as a one way valve to allow flow of fluid from the compression chamber to the rebound chamber through one or more compression flow passages in the piston during the compression stroke of the suspension strut. The rebound stroke valve acts as a one way valve which allows flow of fluid from the rebound chamber to the compression chamber through one or more rebound flow passages in the piston during the rebound stroke of the suspension strut. The piston rod extends out of the tube at one end thereof, and is sealably slidably mounted in that one end. A rebound stop is attached to the piston rod between the piston and the one end of the tube. The rebound stop limits the movement of the piston towards the one end of the tube during the rebound stroke of the suspension strut. Typically, the rebound stop comprises a rigid metal ring which is secured to the piston rod on the piston side of the rebound stop, and an annular bumper of elastomeric material which is engageable with the one end of the tube. During a rebound stroke, the bumper is compressed between a substantially flat surface at the one end of the tube and a substantially flat surface on the metal ring. This arrangement has the disadvantage that a noise can be generated on initial contact and compression of the bumper.